The present invention relates to a trigger type liquid dispenser mounted on a liquid container to dispense or atomize liquid in the container.
A conventional trigger type liquid dispenser is disclosed, for example, in Japanese Patent Publication No. 41726/1979 and Japanese Utility Model Publication No. 920/1986.
These publications disclose a dispenser body detachably engaged with the neck of a liquid container, a pump manually driven by a trigger to intake the liquid in the container in the body, and a nozzle unit for exhausting the pressurized liquid to exhaust the liquid of the container by manually operating the trigger.
The liquid dispenser disclosed in Japanese Patent Publication No. 41726/1979 further employs a pump chamber also used as a spring chamber, and a spring mounted in the pump chamber so that the spring is always dipped directly in the exhausting liquid. Thus, the spring is readily rusted or dissolved in the liquid, and such a dispenser is restricted in its utility.
The liquid dispenser disclosed in Japanese Utility Model Publication No. 920/1986 employs double walled inner and outer cylindrical members, and uses the inner cylindrical member as a pump chamber where a spring mounted in the pump chamber is always dipped in the discharging liquid. This dispenser also has similar drawbacks associated with the above dispenser.
There is also disclosed in Japanese Utility Model Publication No. 29901/1982 a liquid dispenser having a structure where a stopper projects on the side of a nozzle mounted in contact at a fork portion of a trigger. Such an arrangement prevents the trigger from overturning inwardly from the top of the side wall without limiting the structures of the engaging grooves and lugs.
In this dispenser, the trigger is readily removed from the body before the step of assembling the nozzle in case of temporarily assembling the trigger on the body when associating the dispenser to improve the assembling productivity.
The above-said Japanese Utility Model Publication No. 920/1986 discloses an atomizing head (exhaust element) of a trigger unit to be attached on the end of an injecting cylinder (exhausting cylinder).
When assembling a non-conventional dispenser where the trigger is separated from the atomizing head, it is difficult to smoothly position the exhaust element accurately at the assembling position of the body when the exhaust element is not engaged with the end of the exhaust cylinder but covered thereon. Thus, assembly productively is hardly improved.
Further, the conventional trigger type liquid dispenser is constructed as disclosed in Japanese Utility Model Publication No. 920/1981 where the inner cylindrical member is merely inserted into the outer cylindrical member.
In the conventional trigger type liquid dispenser where the inner cylindrical member is merely inserted into the outer cylindrical member, liquid may leak from the engaging surface between the outer cylindrical member and the inner cylindrical member when exhausting liquid by the operation of the trigger, thus reducing the exhausting efficiency. Therefore, a trigger type liquid dispenser which can reduce leakage of liquid from the engaging surface between the outer cylindrical member and the inner cylindrical member is desired.